Fall-plate arrangement for a raschel knitting machine

ABSTRACT

THE FALL-PLATE OF A RASCHEL KNITTING MACHINE IS MOUNTED ON THE GUIDE BAR HANGERS IN SUCH A POSITION THAT THE PLATE IS OBLIQUELY INCLINED TO THE COMMON PLANE OF THE KNITTING NEEDLES WHEN THE HANGER IS IN THE MEDIAN POSITION OF ITS OSCILLATING MOVEMENT. THE MOVEMENT OF THE FALL-PLATE TOWARD AND AWAY FROM THE NEEDLES IS GUIDED IN SUCH A MANNER THAT THE LOWER OPERATING EDGE OF THE PLATE MOVES IN A PATH SUBSTANTIALLY PARALLEL TO THE COMMON NEEDLE PLANE.

K. KOHL FALL-PLATE ARRANGEMENT FOR A RASCHEL KNITTING MACHINE Filed 001;. 31, 1968 2 Sheets-Sheet l INVENTORI KARL ((OHL y l wii AGENT March 9,1971 K. KOHL 14 FIXLL-PLA'IE ARRANGEMENT FOR A RASCHEL KNITTING MACHINE Filed Oct. 31, 1968 2 Sheets-Sheet z INVENTORI 14AM KOHL United States Patent O 3,568,470 FALL-PLATE ARRANGEMENT FOR A RASCHEL KNITTING MACHINE Karl Kohl, Oifenbacher Landstr. 20, Hainstadt (Main), Germany Filed Oct. 31, 1968, Ser. No. 772,139 Claims priority, application Germany, Nov. 3, 1967, P 16 35 874.0 Int. Cl. D04b 23/00 U.S. Cl. 66-86 2 Claims ABSTRACT OF THE DISCLOSURE The fall-plate of a raschel knitting machine is mounted on the guide bar hangers in such a position that the plate is obliquely inclined to the common plane of the knitting needles when the hanger is in the median position of its oscillating movement. The movement of the fall-plate toward and away from the needles is guided in such a manner that the lower operating edge of the plate moves in a path substantially parallel to the common needle plane.

BACKGROUND OF THE INVENTION This invention relates to raschel knitting machines equipped with a fall-plate, and particularly to a fall-plate mechanism which moves the. fall-plate relative to the knitting needles during the operation of the machine.

Fall-plates are mounted on the guide bar hangers of known raschel knitting machines in such a manner that the plate is approximately parallel to the common plane of the knitting needles in the median position of the guide bar hangers. When the yarn guides are swung through the needles by the oscillating movement of the hanger transversely of the needle plane, the lower operating edge of the fall-plate moves transversely of that plane over a distance which is directly related to the amplitude of the guide bar oscillation.

The fall-plate engages yarns threaded on front yarn guides and wrapped about the needles to push these yarns down over the open latches of the knitting needles and on to the fabric loops on the needle stems while the needles are in their top position. When the machine is equipped with numerous operative guide bars, and the amplitude of hanger movement is correspondingly great, the operating lower edge of the fall-plate moves laterally away from the needle plane over a distance sufficient for the transverse component of the tension in the engaged yarns to cause more friction between yarn and needle stem than can be overcome by the tension component which is longitudinal relative to the needles, and the wrapped yarns are not pushed down from the latches.

In order to overcome this problem, it has been necessary heretofore to interrupt the swinging motion of the guide bars and of the associated hangers while the fallplate is still close to the common plane of the knitting needles, and to have the fall-plate perform its stroke in a direction toward the knitting needles during the pause in the swinging motion. The overall operating speed and the output of a knitting machine operated in such a manner are necessarily reduced.

The primary object of this invention is the provision of a fall-plate arrangement which permits the guide bar hangers to oscillate continuously during normal knitting operation, yet keeps the operating edge of the fall-plate near the needle plane during the downward stroke of the plate, that is, during the movement of the plate in a direction toward the knitting needles.

Patented Mar. 9, 1971 "Ice SUMMARY OF THE INVENTION The fall-plate mechanism of the invention is equipped with guiding devices which guide the operating edge of the fall-plate in a path substantially parallel to the common plane of the knitting needles during the oscillating movement of the fall-plate with the guide bar hangers on which the fall plate is mounted.

The distance between the path of the fall-plate edge and the needle plane is readily selected with such an arrangement to tension the front guide yarns engaged by the fall-plate edge longitudinally of the needle elongation.

The exact nature of this invention as well as other objects and advantages thereof will be readily appreciated from consideration of the following specification relating to the annexed drawing.

BRIEF DESCRIPTION OF THE DRAWING In the drawing:

FIG. 1 shows operating elements of a raschel knitting machine of the invention in a perspective view;

FIG. 2 illustrates the fall-plate mechanism of the machine of FIG. 1 in fragmentary front elevation;

FIGS. 2a and 2b show details of the fall-plate mechanism in front elevation and plan view respectively; and

FIG. 3 shows the fall-plate and a needle of the same machine in a perspective view.

DESCRIPTION OF THE PREFERRED EMBODIMENT The drawing shows as much of an otherwise conventional raschel knitting machine as is needed for an understanding of this invention. The guide =bar rocker shaft 10 of the machine is journaled on the supporting machine frame 11 by means of bearings 12 of which only one is shown in FIG. 1. A radial swing lever 13 fixedly fastened to the shaft 10 oscillates the shaft 10 when a connecting rod 15 hinged to the lever 13 reciprocates longitudinally, as indicated by the arrow 14.

The rod 15 is pivotally attached to a transmission lever 16 fulcrumed on a stationary shaft 17 and hingedly connected by a push rod 18 to a truck arm 19 pivoted on a shaft 20 which is an element of the stationary machine frame. The truck arm 19 is oscillated on the shaft 20 by an eccentric cam 21 fixedly mounted on the main camshaft 22 of the machine.

Guide bar hangers 23, of which only one is seen in the drawing, are mounted on the shaft 10 in axially spaced relationship by means of brackets 24. F our guide bars 25a- 25d are supported on the hangers 23 and are moved longitudinally during knitting by the non-illustrated pattern mechanism of the machine. The guide bars carry partly illustrated rows of yarn guides 26. The structure described so far is conventional.

The hangers 23 also support a fall-plate bar 27 between the yarn guide 250 and 25d, and a fall plate 28 which is a thin piece of sheet metal extending over the entire width of the knitting machine and fixedly fastened to the bar 27. As is shown in FIG. 2, rods 29, of which only one is seen in the drawing, extend upwardly from the bar 27, and each rod 29 is slidably guided parallel to the plane of the fall-plate 28 in a ball bearing 30 on a yoke 31 fixedly fastened to a guide bar hanger 23, the direction of rod movement being indicated by an arrow 32. The fall-plate bar 27 is suspended from the rods 29 by means of short spiral springs 33.

A link 34 is hinged to the upper end of each rod 29 and to one arm of an angle lever 35 whose other arm is pivoted to the yoke 31, and whose fulcrum is pivoted parallel to control bars 36a, 36b, parallel to the shaft 10 and guided by the levers 35 for longitudinal reciprocating movement, as indicated by the arrow 37 Reverting to FIG. 1, it is seen that one longitudinal end of each control bar 36a, 36b, is hingedly connected by a universal joint 38a to a push rod 38 which is reciprocated longitudinally by a rocker 39 attached to the machine frame 11 by a pivot pin 40. A connecting rod 41 hingedly couples the rocker 39 to a truck arm 42 pivotally mounted on the shaft 20 and oscillated during normal operation of the machine by an eccentric cam 21a on the camshaft 22.

FIG. 1 also shows the conventional needle mechanism of the machine. The knitting needles 44 are mounted in a row on the single needle bar 43 which is moved up and down by a connecting rod 45 hinged to a cam-operated truck arm 46 mounted on the shaft 20.

The operation of the afore-described apparatus is shown in FIG. 3. The lower operating edge 47 of the fall plate 28 is moved between the fully drawn lowermost position of the fall plate 28 and the topmost position, indicated in broken lines, in the direction of the arrow 48 while the guide bar hanger and the associated front yarn guide 25d swing, as is shown by the arrow 49. Because of the inclination of the plate 28 to the common plane 50 of the latch needles 44, the path 51 of the edge 47 is practically parallel to the plane 50. The distance of the edge 47 from the needle axes thus remains practically constant and very short during the downward movement of the fall-plate. The tension of the non-illustrated yarn threaded through the front yarn guide 25d thus has a re- 4 dominant component longitudinal of the knitting needle stern.

What is claimed is:

1. In a raschel knitting machine having a row of knitting needles extending in a common plane, a guide bar mechanism including a hanger, a plurality of guide bars elongated in a direction parallel to said plane and mounted on said hanger, means for oscillating said hanger transversely of said plane about a median position thereof, a fall-plate mounted on said hanger for oscillating movement therewith, said fall-plate having an operating edge parallel to said plane and adjacent said needles, and actuating means for moving said fall-plate relative to said hanger in a direction toward and away from said needles, the improvement which comprises mounting means mounting means mounting said fall-plate on said hanger in a position in which said plate is obliquely inclined relative to said common plane during said moving of said fallplate by said actuating means.

2. In a machine as set forth in claim 1, said actuating means including guide means guiding said operating edge in a path substantially parallel to said plane during the oscillating movement of said fall-plate with said hanger and while said plate is obliquely inclined relative to said common plane.

References Cited UNITED STATES PATENTS 3,410,113 11/1968 Bassist 6684 3,469,419 9/1969 Kohl 66-86XR RONALD FELDBAUM, Primary Examiner 

